A solid-state image pickup device, for example, is used in an image pickup apparatus such as a digital still camera and a video camera, and an electronic apparatus such as a portable terminal having an imaging function. As an example of the solid-state image pickup device, there is a complementary MOS (CMOS) image sensor which reads charges accumulated in a photodiode serving as a photoelectric conversion element via a metal oxide semiconductor (MOS) transistor.
Generally, the CMOS image sensor transfers the charges accumulated in the photodiode of each pixel to a charge voltage conversion section via a transfer transistor, and converts the charges into a voltage to read the signal.
In such a CMOS image sensor, there is a proposed configuration in which capacitance is added to the charge voltage conversion section via a transistor, and the capacitance of the charge voltage conversion section is configured to be variable. Specifically, there is a proposed configuration in which the charge voltage conversion section is divided into two parts, and a capacitor is added to one part (see, for example, PTLs 1 to 3).
With this configuration, the technology of PTL 1 can switch a gain for converting charges into a voltage, and realize an improvement in a fill factor. In addition, the technologies of PTLs 2 and 3 can accumulate charges generated by the photoelectric conversion element during an exposure period in the capacitor added to the charge voltage conversion section, so that it can make a dynamic range expand toward a high illumination region.